Powered machines often include one or more turbochargers for compressing a fluid such as air, which is then supplied to combustion cylinders of a power source. Exhaust gases are directed to and drive a turbine wheel of the turbocharger. The turbine wheel may be connected to a shaft that drives a compressor wheel. Ambient air is compressed by the compressor wheel and fed into the intake manifold of the power source, thereby increasing power output.
As the turbine wheel rotates, centrifugal force created may exceed a material rupture threshold and the turbine wheel may rupture, thereby releasing kinetic energy from the rotating wheel into the turbocharger and surrounding components. Ordinarily, this kinetic energy is contained by adding material to the casing surrounding the turbine wheel in its rupture plane. However, the addition of this material can add significant weight or cost to the powered machine to which such turbocharger is attached. Further, the addition of material to the rupture plane may cause undesirable fatigue related to thermomechanical phenomena in such turbocharger. Accordingly, turbocharger designers are continually seeking ways to absorb kinetic energy of turbine wheel ruptures without significantly increasing the amount of the surrounding casing material.
One attempt to minimize the amount of material released from a device, and thereby decrease the amount of kinetic energy that needs to be contained, is disclosed in Chinese Patent Application having publication number CN204041121 (the '121 patent application). The '121 patent application is directed to a bladed disk (a.k.a., a blisk) for an aircraft engine. Material fatigue may cause the blisk to fracture, and the fractured portion may impinge upon other portions of the aircraft engine or aircraft. In order to increase passenger safety, the '121 patent application describes a ceramic blisk with a concave portion positioned radially outward a root portion and a blade. Consequently, in the event of a failure, the section radially outward the root portion may fracture, and therefore less material is likely to impinge upon other portions of the aircraft engine and aircraft.
While arguably effective for its specific purpose, the '121 patent application is related to aircraft engines, and in no way related to turbochargers. Accordingly, the '121 patent in no way describes, or alludes to, a turbine for a turbocharger. Moreover, the '121 patent in no way describes or alludes to any additional modifications of its blisk, or other features of a system that may be used in conjunction with its modified blisk, to contain the kinetic energy released in the event of a rupture.
The present disclosure is directed to overcoming one or more problems set forth above and/or other problems associated with the prior art.